ABB, the power and automation technology group, announced in September that it will install an integrated solar-diesel microgrid at its Longmeadow premises in Johannesburg, South Africa.
“This kind of integrated product — it’s almost the UPS equivalent of a hybrid car — is already starting to be seen as the way forward for energy storage in the future,” says one commentator. “Mix and match will be the way forward for energy storage at the grid level.”
The 96,000 square meter facility houses the company’s country headquarters as well as medium voltage switchgear manufacturing and protection panel assembly facilities, with around 1,000 employees. This includes a rooftop solar photovoltaic field and a PowerStore grid stabilizer, that will help to maximize the use of solar energy and ensure uninterrupted power supply.
A 750 kW rooftop PV plant and a 1 MVA/380 kWh battery-based PowerStore will be added to the existing back-up diesel generators. This will enhance the use of renewable energy and provide continuity of supply when power supply is disrupted and during transitions from grid to island operation.
“Power shortages, availability of renewable energy sources like wind and solar, fossil fuel price volatility and environmental concerns are leading to the search for sustainable solutions and there are thousands of facilities across South Africa and the continent that could leverage microgrid technologies to address these challenges,” says ABB.
South Africa has the highest electricity consumption in the sub-Saharan region and demand continues to outpace supply. As highlighted in a recent report by McKinsey & Company, sub-Saharan Africa will consume nearly 1,600 terawatt hours of electricity by 2040 — a four-fold increase on 2010 consumption.
This is based on assumptions such as a fivefold increase in GDP, a doubling of population, electricity-access levels reaching more than 70% by 2040, and increased urbanization. This would imply that by 2040, sub-Saharan Africa could consume as much electricity as India and Latin America combined did in 2010.
“Alongside traditional and renewable generation, microgrids are increasingly being deployed to provide electricity to remote or isolated areas” said Claudio Facchin, president of ABB’s Power Systems division. ”They can also serve as a flexible backup source for industrial and commercial facilities and help address power disruptions.”
ABB says its comprehensive microgrid offering includes a range of technologies for off-grid applications like islands, isolated grids, remote communities as well as commercial and industrial facilities, ensuring utility-grade power quality and grid stability.
“We have a broad range of microgrid solutions including automation and intelligent control and stabilization systems. They enable very high levels of wind and solar power penetration in diesel-powered grids, reducing dependency on fossil fuel supplies and curtailing CO2 emissions,” an official says.
Smart PowerFlow project to demonstrate how batteries can cost-efficiently reinforce low
voltage grids for high shares of renewable power
A team of four — Younicos, a German US technology company, Bavarian distribution grid operator LEW distribution, the Reiner Lemoine Institute and SMA Solar Technology — are to investigate the potential of using batteries at the low voltage level to alleviate local grids. As part of a project called Smart PowerFlow, the partners unveiled a 200kW/400kWhr vanadium redox flow battery in September.
Germany’s energy transformation in the past few years to renewables is felt particularly strongly in southern Bavaria’s regional power grids. Originally, the networks were set up to distribute centrally produced power. Today they also gather electricity from numerous photovoltaic systems, especially in the region of Bavarian Swabia where the LVN grid area is. “By temporarily storing the excess electricity from renewable energy locally and delivering it back into the local network when required, the battery storage system should help to create an efficient, local balance between generation and consumption,” says a joint statement from the firms.
The Smart PowerFlow project will investigate to what extent a regional network expansion can be avoided through the use of battery storage. The system supports local voltage control, so that future network expansion costs are minimized while at the same time the capacity of the distribution network to integrate renewable energy is maximized.
In addition, the project partners want to test various control modes and evaluate associated revenue streams such as voltage control, frequency control, reactive power management and participation in the frequency regulation market. This is to show that intelligent battery systems at the distribution level are an economic means of efficiently reinforcing grids.
The project location — Tussenhausen — was selected from 80 possible locations. Several photovoltaic systems feed into the grid with a maximum output of 560kw. At the same time a correspondingly large local network transformer is present. The battery has been erected on the outskirts of the town near the local power station.